Conventional transmissions are described in, for example, FR-A-2 970 209. According to such known solutions, an overrunning clutch is interposed between a hub drivingly connected for rotation with a secondary shaft of the transmission and a ring gear drivingly connected for rotation with a drive shaft of the internal combustion engine, whereby in the engaged condition of the overrunning clutch the secondary shaft is drivingly connected for rotation with the drive shaft of the internal combustion engine.